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Cisco Sx350, SG350X, SG350XG, Sx550X & SG550XG Series Managed Switches, Firmware Release 2.2.5.x 408
 
IP Configuration: VRRP 
NOTE This feature is only supported in the 550 family of switches.
This chapter describes how Virtual Router Redundancy Protocol (VRRP) works and how to 
configure virtual routers running VRRP through the WEB GUI. 
It covers the following topics:
•Overview
• VRRP Topology
• Configurable Elements of VRRP
• Configuring VRRP
Overview
VRRP is an election and redundancy protocol that dynamically assigns the responsibility of a 
virtual router to one of the physical routers on a LAN. This increase the availability and 
reliability of routing paths in the network. 
In VRRP, one physical router in a virtual router is elected as the master, with the other physical 
router of the same virtual router acting as backups in case the master fails. The physical routers 
are referred as VRRP routers.
The default gateway of a participating host is assigned to the virtual router instead of a 
physical router. If the physical router that is routing packets on behalf of the virtual router 
fails, another physical router is selected to automatically replace it. The physical router that is 
forwarding packets at any given time is called the master router.
VRRP also enables load sharing of traffic. Traffic can be shared equitably among available 
routers by configuring VRRP in such a way that traffic to and from LAN clients are shared by 
multiple routers.